Light emitting diode (LED) lighting technology has taken the world by storm in recent years, but nowhere like in Japan. LEDs have, in fact, become so pervasive that the country may soon face a saturation point.

High reliability, low power consumption, long life, low pollution, and falling production costs have enabled LED use to spread rapidly. By 2015, global market penetration was expected to reach 31%, according to industry news source LED Inside.

In Japan, where LED industry policies began with the "21st Century Lighting Project" in 1998, the buildout has been even more dramatic, with penetration soon hitting 50%. That figure is seen at 70% by 2020; the government targets near 100% adoption by 2030.

"The 2011 Tohoku earthquake and tsunami (in Japan's northeast) provided a big emotional kick to national energy policy, after the government asked the general population to cut household energy consumption by double-digits when all the nuclear plants were switched off," says Eiji Fujiwara, senior sales executive at industrial LED-maker DNL Lighting.

Faced with rolling brownouts in Tokyo and other big cities, this goal was accomplished almost overnight, he notes, as people rushed to replace fluorescent bulbs with LEDs. LEDs typically last four to five times longer than fluorescents (40-50 times longer than incandescents) and consume 40% to 80% less electricity, respectively.

These days, almost all of Japan's new high rise buildings are 100% LED-equipped, while nearly half of the nation's stop signals have switched to LED units. DNL Lighting specializes in an industry-leading, super-thin 8mm LED bulb that has found wide adoption around construction projects and for indirect ambient illumination in high-rise buildings and industrial parks.

Japan is no laggard in developing core LED technology. Three Japanese physicists-- Isamu Akasaki, Hiroshi Amano and Shuji Nakamura-jointly won the Nobel Prize in 2014 for the development of the blue LED, a revolutionary breakthrough that led to the white LED now used around the world.

Improvements in luminosity and efficiency are constant. Recently, over 300 lm/W (lumens per watt) were measured for the most advanced white LEDs, compared with just 16 lm/W for traditional light bulbs and 70 lm/W for fluorescent lamps. Average LED lifespans approaching 100,000 hours are also within reach.

Overall, LED luminescence has doubled over the last five years, while there is still plenty of room for manufacturing costs to fall, meaning that applications should continue to rise, says Mr. Fujiwara. "Ironically, the problem with LEDs is that they are not exactly 'disposable' like the old incandescent bulbs.

Once installed, they rarely need to be replaced, meaning that once Japan goes 'all-LED,' there aren't going to be many places left to sell them at home."

Fortunately for LED manufacturers, overseas markets are primed for growth. A recent McKinsey report predicted that Asia will occupy 45% of the global general lighting market by 2020. China and the U.S. sport commercial LED penetration rates still in the low teens.

Europe is also getting serious about LED conversion; the city of London was last seen on track to replace two-thirds of its 520,000 streetlights with LEDs by this year in one of the most ambitious public modernization projects in the world.

"Once installed, LEDs rarely need to be replaced, meaning that once Japan goes 'all-LED,' there aren't going to be many places left to sell them at home." -- Eiji Fujiwara